AD ADP1612ARMZ-R7 650 khz /1.3 mhz step-up pwm dc-to-dc switching converter Datasheet

650 kHz /1.3 MHz Step-Up
PWM DC-to-DC Switching Converters
ADP1612/ADP1613
FEATURES
TYPICAL APPLICATION CIRCUIT
L1
ADP1612/
ADP1613
VIN
6
VIN
3
EN
7
FREQ
8
SS
D1
ON
OFF
CIN
R1
FB 2
1.3MHz
650kHz
(DEFAULT)
CSS
VOUT
SW 5
R2
COMP 1
GND
RCOMP
4
COUT
CCOMP
06772-001
Current limit
1.4 A for the ADP1612
2.0 A for the ADP 1613
Minimum input voltage
1.8 V for the ADP1612
2.5 V for the ADP1613
Pin-selectable 650 kHz or 1.3 MHz PWM frequency
Adjustable output voltage up to 20 V
Adjustable soft start
Undervoltage lockout
Thermal shutdown
8-lead MSOP
Figure 1. Step-Up Regulator Configuration
APPLICATIONS
TFT LCD bias supplies
Portable applications
Industrial/instrumentation equipment
100
GENERAL DESCRIPTION
80
70
60
50
ADP1612,
ADP1612,
ADP1613,
ADP1613,
40
V OUT = 12V
V OUT = 15V
V OUT = 12V
V OUT = 15V
30
1
10
100
LOAD CURRENT (mA)
1k
06772-009
The ADP1612/ADP1613 operate in current mode pulse-width
modulation (PWM) with up to 94% efficiency. Adjustable
soft start prevents inrush currents when the part is enabled.
The pin-selectable switching frequency and PWM current-mode
architecture allow for excellent transient response, easy noise
filtering, and the use of small, cost-saving external inductors
and capacitors. Other key features include undervoltage lockout
(UVLO), thermal shutdown (TSD), and logic controlled enable.
VIN = 5V
fSW = 1.3MHz
TA = 25°C
90
EFFICIENCY (%)
The ADP1612/ADP1613 are step-up dc-to-dc switching converters with an integrated power switch capable of providing
an output voltage as high as 20 V. With a package height of less
than 1.1 mm, the ADP1612/ADP1613 are optimal for spaceconstrained applications such as portable devices or thin film
transistor (TFT) liquid crystal displays (LCDs).
Figure 2. ADP1612/ADP1613 Efficiency for Various Output Voltages
The ADP1612/ADP1613 are available in the lead-free
8-lead MSOP.
Rev. A
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
www.analog.com
Fax: 781.461.3113
©2009 Analog Devices, Inc. All rights reserved.
ADP1612/ADP1613
TABLE OF CONTENTS
Features .............................................................................................. 1
UnderVoltage Lockout (UVLO) ............................................... 12
Applications ....................................................................................... 1
Enable/Shutdown Control ........................................................ 12
Typical Application Circuit ............................................................. 1
Applications Information .............................................................. 13
General Description ......................................................................... 1
Setting the Output Voltage ........................................................ 13
Revision History ............................................................................... 2
Inductor Selection ...................................................................... 13
Specifications..................................................................................... 3
Choosing the Input and Output Capacitors ........................... 13
Absolute Maximum Ratings............................................................ 4
Diode Selection........................................................................... 14
Thermal Resistance ...................................................................... 4
Loop Compensation .................................................................. 14
Boundary Condition .................................................................... 4
Soft Start Capacitor .................................................................... 15
ESD Caution .................................................................................. 4
Typical Application Circuits ......................................................... 16
Pin Configuration and Function Descriptions ............................. 5
Step-Up Regulator ...................................................................... 16
Typical Performance Characteristics ............................................. 6
Step-Up Regulator Circuit Examples ....................................... 16
Theory of Operation ...................................................................... 11
SEPIC Converter ........................................................................ 22
Current-Mode PWM Operation .............................................. 11
TFT LCD Bias Supply ................................................................ 22
Frequency Selection ................................................................... 11
PCB Layout Guidelines .................................................................. 24
Soft Start ...................................................................................... 11
Outline Dimensions ....................................................................... 25
Thermal Shutdown (TSD)......................................................... 12
Ordering Guide .......................................................................... 25
REVISION HISTORY
9/09—Rev. 0 to Rev. A
Changes to Figure 45 ...................................................................... 17
Changes to Figure 48 and Figure 51 ............................................. 18
Changes to Figure 54 and Figure 57 ............................................. 19
Changes to Figure 60 and Figure 63 ............................................. 20
Changes to Figure 66 and Figure 69 ............................................. 21
Changes to Figure 72 ...................................................................... 22
Changes to Ordering Guide .......................................................... 25
4/09—Revision 0: Initial Version
Rev. A | Page 2 of 28
ADP1612/ADP1613
SPECIFICATIONS
VIN = 3.6 V, unless otherwise noted. Minimum and maximum values are guaranteed for TJ = −40°C to +125°C. Typical values specified
are at TJ = 25°C. All limits at temperature extremes are guaranteed by correlation and characterization using standard statistical quality
control (SQC), unless otherwise noted.
Table 1.
Parameter
SUPPLY
Input Voltage
Quiescent Current
Nonswitching State
Shutdown
Switching State 1
Enable Pin Bias Current
OUTPUT
Output Voltage
Load Regulation
REFERENCE
Feedback Voltage
Line Regulation
ERROR AMPLIFIER
Transconductance
Voltage Gain
FB Pin Bias Current
SWITCH
SW On Resistance
SW Leakage Current
Peak Current Limit 2
OSCILLATOR
Oscillator Frequency
Maximum Duty Cycle
FREQ Pin Current
EN/FREQ LOGIC THRESHOLD
Input Voltage Low
Input Voltage High
SOFT START
SS Charging Current
SS Voltage
UNDERVOLTAGE LOCKOUT (UVLO)
Undervoltage Lockout Threshold
Symbol
Conditions
Min
VIN
ADP1612
ADP1613
1.8
2.5
IQ
VFB = 1.5 V, FREQ = VIN
VFB = 1.5 V, FREQ = GND
VEN = 0 V
FREQ = VIN, no load
FREQ = GND, no load
VEN = 3.6 V
IQSHDN
IQSW
IEN
Max
Unit
5.5
5.5
V
V
1350
1300
2
5.8
4
7
μA
μA
μA
mA
mA
μA
20
V
mV/mA
1.2659
0.24
V
%/V
VFB = 1.3 V
80
60
1
50
μA/V
dB
nA
ISW = 1.0 A
VSW = 20 V
ADP1612, duty cycle = 70%
ADP1613, duty cycle = 70%
130
0.01
1.4
2.0
300
10
1.9
2.5
mΩ
μA
A
A
650
1.3
90
5
720
1.4
kHz
MHz
%
μA
VOUT
900
700
0.01
4
2.2
3.3
VIN
ILOAD = 10 mA to 150 mA, VIN = 3.3 V, VOUT = 12 V
VFB
0.1
1.2041
ADP1612, VIN = 1.8 V to 5.5 V; ADP1613, VIN = 2.5 V to 5.5 V
GMEA
AV
RDSON
ICL
fSW
DMAX
IFREQ
ΔI = 4 μA
FREQ = GND
FREQ = VIN
COMP = open, VFB = 1 V, FREQ = VIN
FREQ = 3.6 V
ADP1612, VIN = 1.8 V to 5.5 V; ADP1613, VIN = 2.5 V to 5.5 V
VIL
VIH
ISS
VSS
0.9
1.3
500
1.1
88
2
1.235
0.07
8
0.3
V
V
6.2
μA
V
1.6
VSS = 0 V
VFB = 1.3 V
3.4
ADP1612, VIN rising
ADP1612, VIN falling
ADP1613, VIN rising
ADP1613, VIN falling
THERMAL SHUTDOWN
Thermal Shutdown Threshold
Thermal Shutdown Hysteresis
1
Typ
This parameter specifies the average current while switching internally and with SW (Pin 5) floating.
Current limit is a function of duty cycle. See the Typical Performance Characteristics section for typical values over operating ranges.
Rev. A | Page 3 of 28
5
1.2
1.70
1.62
2.25
2.16
V
V
V
V
150
20
°C
°C
ADP1612/ADP1613
ABSOLUTE MAXIMUM RATINGS
THERMAL RESISTANCE
Table 2.
Parameter
VIN, EN, FB to GND
FREQ to GND
COMP to GND
SS to GND
SW to GND
Operating Junction Temperature Range
Storage Temperature Range
Soldering Conditions
ESD (Electrostatic Discharge)
Human Body Model
Junction-to-ambient thermal resistance (θJA) of the package is
specified for the worst-case conditions, that is, a device soldered
in a circuit board for surface-mount packages. The junction-toambient thermal resistance is highly dependent on the application
and board layout. In applications where high maximum power
dissipation exists, attention to thermal board design is required.
The value of θJA may vary, depending on PCB material, layout,
and environmental conditions.
Rating
−0.3 V to +6 V
−0.3 V to VIN + 0.3 V
1.0 V to 1.6 V
−0.3 V to +1.3 V
21 V
−40°C to +125°C
−65°C to +150°C
JEDEC J-STD-020
Table 3.
±5 kV
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
Absolute maximum ratings apply individually only, not in
combination.
Package Type
8-Lead MSOP
2-Layer Board1
4-Layer Board1
1
θJA
θJC
Unit
206.9
162.2
44.22
44.22
°C/W
°C/W
Thermal numbers per JEDEC standard JESD 51-7.
BOUNDARY CONDITION
Modeled under natural convection cooling at 25°C ambient
temperature, JESD 51-7, and 1 W power input with 2- and
4-layer boards.
ESD CAUTION
Rev. A | Page 4 of 28
ADP1612/ADP1613
COMP 1
FB 2
EN 3
GND 4
ADP1612/
ADP1613
TOP VIEW
(Not to Scale)
8
SS
7
FREQ
6
VIN
5
SW
06772-002
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
Figure 3. Pin Configuration
Table 4. Pin Function Descriptions
Pin No.
1
2
Mnemonic
COMP
FB
3
4
5
EN
GND
SW
6
VIN
7
FREQ
8
SS
Description
Compensation Input. Connect a series resistor-capacitor network from COMP to GND to compensate the regulator.
Output Voltage Feedback Input. Connect a resistive voltage divider from the output voltage to FB to set the
regulator output voltage.
Enable Input. Drive EN low to shut down the regulator; drive EN high to turn on the regulator.
Ground.
Switching Output. Connect the power inductor from the input voltage to SW and connect the external rectifier
from SW to the output voltage to complete the step-up converter.
Main Power Supply Input. VIN powers the ADP1612/ADP1613 internal circuitry. Connect VIN to the input source
voltage. Bypass VIN to GND with a 10 μF or greater capacitor as close to the ADP1612/ADP1613 as possible.
Frequency Setting Input. FREQ controls the switching frequency. Connect FREQ to GND to program the oscillator
to 650 kHz, or connect FREQ to VIN to program it to 1.3 MHz. If FREQ is left floating, the part defaults to 650 kHz.
Soft Start Timing Capacitor Input. A capacitor connected from SS to GND brings up the output slowly at powerup and reduces inrush current.
Rev. A | Page 5 of 28
ADP1612/ADP1613
TYPICAL PERFORMANCE CHARACTERISTICS
VEN = VIN and TA = 25°C, unless otherwise noted.
100
100
ADP1612
VIN = 3.3V
fSW = 650kHz
TA = 25°C
90
80
EFFICIENCY (%)
70
60
50
VOUT = 5V
VOUT = 12V
VOUT = 15V
40
30
1
10
100
LOAD CURRENT (mA)
1k
1
Figure 4. ADP1612 Efficiency vs. Load Current, VIN = 3.3 V, fSW = 650 kHz
10
100
LOAD CURRENT (mA)
1k
Figure 7. ADP1612 Efficiency vs. Load Current, VIN = 5 V, fSW = 1.3 MHz
100
100
ADP1612
VIN = 3.3V
fSW = 1.3MHz
TA = 25°C
90
ADP1613
VIN = 5V
fSW = 650kHz
TA = 25°C
90
80
EFFICIENCY (%)
80
70
60
50
70
60
50
VOUT = 5V
VOUT = 12V
VOUT = 15V
30
1
10
100
LOAD CURRENT (mA)
VOUT = 12V
VOUT = 15V
VOUT = 20V
40
1k
30
06772-026
40
1
Figure 5. ADP1612 Efficiency vs. Load Current, VIN = 3.3 V, fSW = 1.3 MHz
10
100
LOAD CURRENT (mA)
1k
06772-029
EFFICIENCY (%)
VOUT = 12V
VOUT = 15V
30
06772-012
40
Figure 8. ADP1613 Efficiency vs. Load Current, VIN = 5 V, fSW = 650 kHz
100
100
ADP1612
VIN = 5V
fSW = 650kHz
TA = 25°C
90
ADP1613
VIN = 5V
fSW = 1.3MHz
TA = 25°C
90
80
EFFICIENCY (%)
80
EFFICIENCY (%)
60
06772-028
50
70
70
60
50
70
60
50
40
10
100
LOAD CURRENT (mA)
1k
30
06772-027
30
1
VOUT = 12V
VOUT = 15V
VOUT = 20V
40
VOUT = 12V
VOUT = 15V
Figure 6. ADP1612 Efficiency vs. Load Current, VIN = 5 V, fSW = 650 kHz
1
10
100
LOAD CURRENT (mA)
1k
06772-030
EFFICIENCY (%)
80
ADP1612
VIN = 5V
fSW = 1.3MHz
TA = 25°C
90
Figure 9. ADP1613 Efficiency vs. Load Current, VIN = 5 V, fSW = 1.3 MHz
Rev. A | Page 6 of 28
ADP1612/ADP1613
2.4
3.4
ADP1613
ADP1612
3.2
TA = +25°C
1.8
TA = –40°C
1.6
1.4
1.2
1.8
TA = +85°C
2.3
3.0
TA = +25°C
2.8
2.6
2.4
2.2
2.8
3.3
3.8
INPUT VOLTAGE (V)
4.3
4.8
Figure 10. ADP1612 Switch Current Limit vs. Input Voltage, VOUT = 5 V
2.0
2.5
3.0
3.5
4.0
INPUT VOLTAGE (V)
4.5
Figure 13. ADP1613 Switch Current Limit vs. Input Voltage, VOUT = 5 V
2.6
2.0
ADP1613
ADP1612
1.8
2.4
CURRENT LIMIT (A)
CURRENT LIMIT (A)
TA = –40°C
TA = +85°C
06772-031
CURRENT LIMIT (A)
2.0
06772-010
CURRENT LIMIT (A)
2.2
TA = +25°C
1.6
1.4
TA = +25°C
2.2
TA = –40°C
2.0
TA = –40°C
TA = +85°C
1.2
2.3
2.8
3.3
3.8
4.3
INPUT VOLTAGE (V)
4.8
5.3
1.8
2.5
06772-013
1.0
1.8
Figure 11. ADP1612 Switch Current Limit vs. Input Voltage, VOUT = 8 V
3.0
3.5
4.0
4.5
5.0
5.5
INPUT VOLTAGE (V)
06772-032
TA = +85°C
Figure 14. ADP1613 Switch Current Limit vs. Input Voltage, VOUT = 8 V
1.6
2.6
ADP1613
ADP1612
2.4
1.2
TA = +85°C
1.0
TA = –40°C
2.2
2.0
1.8
TA = +25°C
TA = +85°C
1.6
2.3
2.8
3.3
3.8
4.3
INPUT VOLTAGE (V)
4.8
5.3
1.4
2.5
06772-011
0.8
1.8
Figure 12. ADP1612 Switch Current Limit vs. Input Voltage, VOUT = 15 V
3.0
3.5
4.0
4.5
INPUT VOLTAGE (V)
5.0
5.5
06772-033
TA = –40°C
TA = +25°C
CURRENT LIMIT (A)
CURRENT LIMIT (A)
1.4
Figure 15. ADP1613 Switch Current Limit vs. Input Voltage, VOUT = 15 V
Rev. A | Page 7 of 28
ADP1612/ADP1613
800
6
ADP1612/ADP1613
ADP1612/ADP1613
750
TA = +25°C
QUIESCENT CURRENT (mA)
QUIESCENT CURRENT (µA)
5
700
650
TA = +125°C
600
550
TA = –40°C
TA = +25°C
500
TA = +125°C
4
TA = –40°C
3
2
2.3
2.8
3.3
3.8
4.3
INPUT VOLTAGE (V)
4.8
5.3
1
1.8
06772-014
400
1.8
Figure 16. ADP1612/ADP1613 Quiescent Current vs. Input Voltage,
Nonswitching, fSW = 650 kHz
2.3
2.8
3.3
3.8
4.3
INPUT VOLTAGE (V)
4.8
06772-018
450
5.3
Figure 19. ADP1612/ADP1613 Quiescent Current vs. Input Voltage, Switching,
fSW = 1.3 MHz
800
250
ISW = 1A
ADP1612/ADP1613
ADP1612/ADP1613
230
210
700
TA = +30°C
190
TA = +125°C
RDSON (mΩ)
QUIESCENT CURRENT (µA)
750
650
TA = +85°C
170
150
130
600
TA = –40°C
110
TA = +25°C
550
90
2.8
3.3
3.8
4.3
INPUT VOLTAGE (V)
4.8
5.3
06772-017
2.3
70
1.8
Figure 17. ADP1612/ADP1613 Quiescent Current vs. Input Voltage,
Nonswitching, fSW = 1.3 MHz
2.3
2.8
3.3
3.8
4.3
INPUT VOLTAGE (V)
4.8
06772-016
TA = –40°C
500
1.8
5.3
Figure 20. ADP1612/ADP1613 On Resistance vs. Input Voltage
3.5
250
ISW = 1A
ADP1612/ADP1613
ADP1612/ADP1613
230
VIN = 1.8V
210
TA = +25°C
190
2.5
RDSON (mΩ)
QUIESCENT CURRENT (mA)
3.0
TA = +125°C
2.0
TA = –40°C
170
VIN = 2.5V
150
130
110
1.5
VIN = 3.6V
90
2.8
3.3
3.8
4.3
INPUT VOLTAGE (V)
4.8
5.3
70
–40
06772-015
2.3
Figure 18. ADP1612/ADP1613 Quiescent Current vs. Input Voltage, Switching,
fSW = 650 kHz
Rev. A | Page 8 of 28
–15
10
35
TEMPERATURE (°C)
60
85
Figure 21. ADP1612/ADP1613 On Resistance vs. Temperature
06772-019
VIN = 5.5V
1.0
1.8
ADP1612/ADP1613
660
5.1
ADP1612/ADP1613
ADP1612/ADP1613
650
5.0
TA = +25°C
VIN = 1.8V
SS PIN CURRENT (µA)
FREQUENCY (kHz)
640
630
620
TA = +125°C
610
4.9
VIN = 5.5V
4.8
VIN = 3.6V
4.7
600
4.6
590
2.3
2.8
3.3
3.8
4.3
INPUT VOLTAGE (V)
4.8
5.3
4.5
–40
06772-020
580
1.8
Figure 22. ADP1612/ADP1613 Frequency vs. Input Voltage, fSW = 650 kHz
80
110
92.8
ADP1612/ADP1613
ADP1612/ADP1613
TA = +25°C
1.30
92.6
MAXIMUM DUTY CYCLE (%)
1.28
1.26
1.24
TA = –40°C
1.22
1.20
1.18
TA = +125°C
TA = +125°C
92.4
TA = +25°C
92.2
92.0
TA = –40°C
91.8
91.6
2.3
2.8
3.3
3.8
4.3
INPUT VOLTAGE (V)
4.8
5.3
91.2
1.8
06772-023
1.14
1.8
Figure 23. ADP1612/ADP1613 Frequency vs. Input Voltage, fSW = 1.3 MHz
2.3
2.8
3.3
3.8
4.3
INPUT VOLTAGE (V)
4.8
5.3
06772-022
91.4
1.16
Figure 26. ADP1612/ADP1613 Maximum Duty Cycle vs. Input Voltage,
fSW = 650 kHz
93.4
7
ADP1612/ADP1613
ADP1612/ADP1613
TA = +125°C
93.2
MAXIMUM DUTY CYCLE (%)
6
TA = +125°C
5
4
3
2
TA = +25°C
1
TA = –40°C
1.0
1.5
2.0 2.5 3.0 3.5
EN PIN VOLTAGE (V)
4.0
4.5
5.0
5.5
92.6
TA = –40°C
92.4
92.2
92.0
Figure 24. ADP1612/ADP1613 EN Pin Current vs. EN Pin Voltage
91.6
1.8
06772-021
0.5
92.8
91.8
0
0
TA = +25°C
93.0
2.3
2.8
3.3
3.8
4.3
INPUT VOLTAGE (V)
4.8
5.3
06772-025
FREQUENCY (MHz)
20
50
TEMPERATURE (°C)
Figure 25. ADP1612/ADP1613 SS Pin Current vs. Temperature
1.32
EN PIN CURRENT (µA)
–10
06772-024
TA = –40°C
Figure 27. ADP1612/ADP1613 Maximum Duty Cycle vs. Input Voltage,
fSW = 1.3 MHz
Rev. A | Page 9 of 28
ADP1612/ADP1613
T
T OUTPUT VOLTAGE (5V/DIV)
OUTPUT VOLTAGE (5V/DIV)
VIN = 5V
VOUT = 12V
ILOAD = 20mA
L = 6.8µH
fSW = 1.3MHz
COUT = 10µF
INDUCTOR CURRENT
(200mA/DIV)
SWITCH VOLTAGE (10V/DIV)
VIN = 5V
VOUT = 12V
ILOAD = 250mA
L = 6.8µH
fSW = 1.3MHz
INDUCTOR CURRENT (2A/DIV)
SWITCH VOLTAGE (10V/DIV)
TIME (400ns/DIV)
TIME (20ms/DIV)
Figure 28. ADP1612/ADP1613 Switching Waveform in Discontinuous
Conduction Mode
Figure 31. ADP1612/ADP1613 Start-Up from VIN, CSS =100 nF
T
T
OUTPUT VOLTAGE (5V/DIV)
INDUCTOR CURRENT
(500mA/DIV)
06772-037
06772-034
EN PIN VOLTAGE (5V/DIV)
OUTPUT VOLTAGE (5V/DIV)
VIN = 5V
VOUT = 12V
ILOAD = 200mA
L = 6.8µH
fSW = 1.3MHz
COUT = 10µF
SWITCH VOLTAGE (10V/DIV)
VIN = 5V
VOUT = 12V
ILOAD = 250mA
L = 6.8µH
fSW = 1.3MHz
SWITCH VOLTAGE (10V/DIV)
06772-035
EN PIN VOLTAGE (5V/DIV)
TIME (400ns/DIV)
Figure 29. ADP1612/ADP1613 Switching Waveform in Continuous
Conduction Mode
TIME (400µs/DIV)
06772-038
INDUCTOR CURRENT (500mA/DIV)
Figure 32. ADP1612/ADP1613 Start-Up from Shutdown, CSS = 33 nF
T
T
OUTPUT VOLTAGE (5V/DIV)
SWITCH VOLTAGE (10V/DIV)
VIN = 5V
VOUT = 12V
ILOAD = 250mA
L = 6.8µH
fSW = 1.3MHz
SWITCH VOLTAGE (10V/DIV)
INDUCTOR CURRENT (500mA/DIV)
EN PIN VOLTAGE (5V/DIV)
EN PIN VOLTAGE (5V/DIV)
TIME (20ms/DIV)
06772-036
INDUCTOR CURRENT (2A/DIV)
Figure 30. ADP1612/ADP1613 Start-Up from VIN, CSS =33 nF
TIME (400µs/DIV)
06772-039
OUTPUT VOLTAGE (5V/DIV)
VIN = 5V
VOUT = 12V
ILOAD = 250mA
L = 6.8µH
fSW = 1.3MHz
Figure 33. ADP1612/ADP1613 Start-Up from Shutdown, CSS = 100 nF
Rev. A | Page 10 of 28
ADP1612/ADP1613
THEORY OF OPERATION
L1
VIN
>1.6V
CIN
<0.3V
VIN
6
7
+
VIN
D
COMPARATOR
VOUT
R1
ERROR
AMPLIFIER
FB
VOUT
DREF
5µA
DRIVER
VIN
S
Q
UVLOREF
VSS
N1
R
TSD
COMPARATOR
5µA
8
D1
COUT
UVLO
COMPARATOR
RCOMP
SS
SW
OSCILLATOR
1
CCOMP
5
CURRENT
SENSING
PWM
COMPARATOR
VBG
COMP
A
+
2
R2
FREQ
TSENSE
SOFT
START
BG
RESET
TREF
BAND GAP
CSS
AGND
1.1MΩ
ADP1612/AD1613
AGND
4
GND
>1.6V
<0.3V
06772-003
EN
3
Figure 34. Block Diagram with Step-Up Regulator Application Circuit
The ADP1612/ADP1613 current-mode step-up switching
converters boost a 1.8 V to 5.5 V input voltage to an output
voltage as high as 20 V. The internal switch allows a high
output current, and the high 650 kHz/1.3 MHz switching
frequency allows for the use of tiny external components.
The switch current is monitored on a pulse-by-pulse basis to
limit it to 1.4 A typical (ADP1612) or 2.0 A typical (ADP1613).
FREQUENCY SELECTION
CURRENT-MODE PWM OPERATION
The ADP1612/ADP1613 utilize a current-mode PWM control
scheme to regulate the output voltage over all load conditions.
The output voltage is monitored at FB through a resistive voltage
divider. The voltage at FB is compared to the internal 1.235 V
reference by the internal transconductance error amplifier to
create an error voltage at COMP. The switch current is internally
measured and added to the stabilizing ramp. The resulting sum
is compared to the error voltage at COMP to control the PWM
modulator. This current-mode regulation system allows fast
transient response, while maintaining a stable output voltage.
By selecting the proper resistor-capacitor network from COMP
to GND, the regulator response is optimized for a wide range of
input voltages, output voltages, and load conditions.
The frequency of the ADP1612/ADP1613 is pin-selectable
to operate at either 650 kHz to optimize the regulator for high
efficiency or at 1.3 MHz for use with small external components.
If FREQ is left floating, the part defaults to 650 kHz. Connect
FREQ to GND for 650 kHz operation or connect FREQ to VIN
for 1.3 MHz operation. When connected to VIN for 1.3 MHz
operation, an additional 5 μA, typical, of quiescent current is
active. This current is turned off when the part is shutdown.
SOFT START
To prevent input inrush current to the converter when the part is
enabled, connect a capacitor from SS to GND to set the soft start
period. Once the ADP1612/ADP1613 are turned on, SS sources
5 μA, typical, to the soft start capacitor (CSS) until it reaches
1.2 V at startup. As the soft start capacitor charges, it limits the
peak current allowed by the part. By slowly charging the soft
start capacitor, the input current ramps slowly to prevent it
from overshooting excessively at startup. When the ADP1612/
ADP1613 are in shutdown mode (EN ≤ 0.3 V), a thermal shutdown event occurs, or the input voltage is below the falling
undervoltage lockout voltage, SS is internally shorted to GND
to discharge the soft start capacitor.
Rev. A | Page 11 of 28
ADP1612/ADP1613
THERMAL SHUTDOWN (TSD)
ENABLE/SHUTDOWN CONTROL
The ADP1612/ADP1613 include TSD protection. If the die
temperature exceeds 150°C (typical), TSD turns off the NMOS
power device, significantly reducing power dissipation in the
device and preventing output voltage regulation. The NMOS
power device remains off until the die temperature reduces to
130°C (typical). The soft start capacitor is discharged during
TSD to ensure low output voltage overshoot and inrush
currents when regulation resumes.
The EN input turns the ADP1612/ADP1613 regulator on or
off. Drive EN low to turn off the regulator and reduce the
input current to 0.01 μA, typical. Drive EN high to turn on
the regulator.
UNDERVOLTAGE LOCKOUT (UVLO)
If the input voltage is below the UVLO threshold, the ADP1612/
ADP1613 automatically turn off the power switch and place
the part into a low power consumption mode. This prevents
potentially erratic operation at low input voltages and prevents
the power device from turning on when the control circuitry
cannot operate it. The UVLO levels have ~100 mV of hysteresis
to ensure glitch free startup.
When the step-up dc-to-dc switching converter is in shutdown
mode (EN ≤ 0.3 V), there is a dc path from the input to the output
through the inductor and output rectifier. This causes the output
voltage to remain slightly below the input voltage by the forward
voltage of the rectifier, preventing the output voltage from dropping
to ground when the regulator is shutdown. Figure 37 provides a
circuit modification to disconnect the output voltage from the
input voltage at shutdown.
Regardless of the state of the EN pin, when a voltage is applied to
VIN of the ADP1612/ADP1613, a large current spike occurs due
to the nonisolated path through the inductor and diode between
VIN and VOUT. The high current is a result of the output capacitor
charging. The peak value is dependent on the inductor, output
capacitor, and any load active on the output of the regulator.
Rev. A | Page 12 of 28
ADP1612/ADP1613
APPLICATIONS INFORMATION
SETTING THE OUTPUT VOLTAGE
The ADP1612/ADP1613 feature an adjustable output voltage
range of VIN to 20 V. The output voltage is set by the resistor
voltage divider, R1 and R2, (see Figure 34) from the output
voltage (VOUT) to the 1.235 V feedback input at FB. Use the
following equation to determine the output voltage:
VOUT = 1.235 × (1 + R1/R2)
(1)
For CCM duty cycles greater than 50% that occur with input
voltages less than one-half the output voltage, slope compensation is required to maintain stability of the current-mode
regulator. For stable current-mode operation, ensure that the
selected inductance is equal to or greater than the minimum
calculated inductance, LMIN, for the application parameters in
the following equation:
L > L MIN =
Choose R1 based on the following equation:
− 1.235 ⎞
⎛V
R1 = R2 × ⎜ OUT
⎟
1.235
⎝
⎠
(2)
INDUCTOR SELECTION
The inductor is an essential part of the step-up switching
converter. It stores energy during the on time of the power
switch, and transfers that energy to the output through the
output rectifier during the off time. To balance the tradeoffs
between small inductor current ripple and efficiency, inductance values in the range of 4.7 μH to 22 μH are recommended.
In general, lower inductance values have higher saturation
current and lower series resistance for a given physical size.
However, lower inductance results in a higher peak current
that can lead to reduced efficiency and greater input and/or
output ripple and noise. A peak-to-peak inductor ripple current
close to 30% of the maximum dc input current typically yields
an optimal compromise.
For determining the inductor ripple current in continuous
operation, the input (VIN) and output (VOUT) voltages determine
the switch duty cycle (D) by the following equation:
D=
VOUT − VIN
(3)
VOUT
D
(4)
f SW
The inductor ripple current (ΔIL) in steady state is calculated by
ΔI L =
VIN × t ON
L
(5)
Solve for the inductance value (L) by the following equation:
L=
VIN × t ON
ΔI L
(7)
2.7 × f SW
Inductors smaller than the 4.7 μH to 22 μH recommended
range can be used as long as Equation 7 is satisfied for the given
application. For input/output combinations that approach the
90% maximum duty cycle, doubling the inductor is recommended to ensure stable operation. Table 5 suggests a series
of inductors for use with the ADP1612/ADP1613.
Table 5. Suggested Inductors
Manufacturer
Sumida
Coilcraft
Toko
Würth
Elektronik
Part Series
CMD4D11
CDRH4D28CNP
CDRH5D18NP
CDRH6D26HPNP
DO3308P
DO3316P
D52LC
D62LCB
D63LCB
WE-TPC
WE-PD, PD2, PD3, PD4
Dimensions
L × W × H (mm)
5.8 × 4.4 × 1.2
5.1 × 5.1 × 3.0
6.0 × 6.0 × 2.0
7.0 × 7.0 × 2.8
12.95 × 9.4 × 3.0
12.95 × 9.4 × 5.21
5.2 × 5.2 × 2.0
6.2 × 6.3 × 2.0
6.2 × 6.3 × 3.5
Assorted
Assorted
CHOOSING THE INPUT AND OUTPUT CAPACITORS
Using the duty cycle and switching frequency, fSW, determine
the on time by the following equation:
t ON =
(VOUT − 2 × VIN )
(6)
The ADP1612/ADP1613 require input and output bypass capacitors to supply transient currents while maintaining constant
input and output voltages. Use a low equivalent series resistance
(ESR), 10 μF or greater input capacitor to prevent noise at the
ADP1612/ADP1613 input. Place the capacitor between VIN
and GND as close to the ADP1612/ADP1613 as possible.
Ceramic capacitors are preferred because of their low ESR
characteristics. Alternatively, use a high value, medium ESR
capacitor in parallel with a 0.1 μF low ESR capacitor as close
to the ADP1612/ADP1613 as possible.
Ensure that the peak inductor current (the maximum input
current plus half the inductor ripple current) is below the rated
saturation current of the inductor. Likewise, make sure that the
maximum rated rms current of the inductor is greater than the
maximum dc input current to the regulator.
Rev. A | Page 13 of 28
ADP1612/ADP1613
The output capacitor maintains the output voltage and supplies
current to the load while the ADP1612/ADP1613 switch is on.
The value and characteristics of the output capacitor greatly
affect the output voltage ripple and stability of the regulator. A
low ESR ceramic dielectric capacitor is preferred. The output
voltage ripple (ΔVOUT) is calculated as follows:
ΔVOUT =
I ×t
QC
= L ON
COUT
COUT
(8)
where:
QC is the charge removed from the capacitor.
tON is the on time of the switch.
COUT is the output capacitance.
IL is the average inductor current.
t ON =
D
f SW
I L × (VOUT − VIN )
f SW × VOUT × ΔVOUT
(10)
The regulator loop gain is
AVL =
(11)
The output rectifier conducts the inductor current to the output
capacitor and load while the switch is off. For high efficiency,
minimize the forward voltage drop of the diode. For this reason,
Schottky rectifiers are recommended. However, for high voltage,
high temperature applications, where the Schottky rectifier
reverse leakage current becomes significant and can degrade
efficiency, use an ultrafast junction diode.
Ensure that the diode is rated to handle the average output
load current. Many diode manufacturers derate the current
capability of the diode as a function of the duty cycle. Verify
that the output diode is rated to handle the average output
load current with the minimum duty cycle. The minimum
duty cycle of the ADP1612/ADP1613 is
VOUT
V
VFB
× IN × G MEA × Z COMP × GCS × Z OUT
VOUT VOUT
(14)
where:
AVL is the loop gain.
VFB is the feedback regulation voltage, 1.235 V.
VOUT is the regulated output voltage.
VIN is the input voltage.
GMEA is the error amplifier transconductance gain.
ZCOMP is the impedance of the series RC network from COMP
to GND.
GCS is the current sense transconductance gain (the inductor
current divided by the voltage at COMP), which is internally
set by the ADP1612/ADP1613.
ZOUT is the impedance of the load and output capacitor.
(12)
where VIN(MAX) is the maximum input voltage.
The following are suggested Schottky diode manufacturers:
•
•
(13)
To stabilize the regulator, ensure that the regulator crossover
frequency is less than or equal to one-fifth of the right-half
plane zero.
DIODE SELECTION
VOUT − VIN ( MAX )
2
⎞ R LOAD
⎟ ×
⎟ 2π × L
⎠
(9)
Multilayer ceramic capacitors are recommended for this
application.
D MIN =
The step-up converter produces an undesirable right-half plane
zero in the regulation feedback loop. This requires compensating
the regulator such that the crossover frequency occurs well
below the frequency of the right-half plane zero. The righthalf plane zero is determined by the following equation:
where:
FZ(RHP) is the right-half plane zero.
RLOAD is the equivalent load resistance or the output voltage
divided by the load current.
Choose the output capacitor based on the following equation:
C OUT ≥
The ADP1612/ADP1613 use external components to
compensate the regulator loop, allowing optimization of
the loop dynamics for a given application.
⎛ V
FZ (RHP ) = ⎜⎜ IN
⎝ VOUT
and
− VIN
V
D = OUT
VOUT
LOOP COMPENSATION
ON Semiconductor
Diodes, Inc.
Rev. A | Page 14 of 28
ADP1612/ADP1613
To determine the crossover frequency, it is important to note
that, at that frequency, the compensation impedance (ZCOMP)
is dominated by a resistor, and the output impedance (ZOUT) is
dominated by the impedance of an output capacitor. Therefore,
when solving for the crossover frequency, the equation (by
definition of the crossover frequency) is simplified to
V
VFB
× IN × G MEA × RCOMP × GCS ×
VOUT VOUT
1
=1
2π × f C × C OUT
AVL =
(15)
where:
fC is the crossover frequency.
RCOMP is the compensation resistor.
2π × f C × C OUT × (VOUT )2
(16)
VFB × VIN × G MEA × GCS
where:
VFB = 1.235 V.
GMEA = 80 μA/V.
GCS = 13.4 A/V.
RCOMP
2
π × f C × RCOMP
(18)
where CCOMP is the compensation capacitor.
ERROR
AMPLIFIER
COMP
gm
VBG
ESR × C OUT
RCOMP
(19)
For low ESR output capacitance such as with a ceramic
capacitor, C2 is optional. For optimal transient performance,
RCOMP and CCOMP might need to be adjusted by observing the
load transient response of the ADP1612/ADP1613. For most
applications, the compensation resistor should be within the
range of 4.7 kΩ to 100 kΩ and the compensation capacitor
should be within the range of 100 pF to 3.3 nF.
1
RCOMP
06772-004
C2
CCOMP
Upon startup (EN ≥ 1.6 V), the voltage at SS ramps up slowly
by charging the soft start capacitor (CSS) with an internal 5 μA
current source (ISS). As the soft start capacitor charges, it limits
the peak current allowed by the part to prevent excessive overshoot at startup. The necessary soft start capacitor, CSS, for a
specific overshoot and start-up time can be calculated for the
maximum load condition when the part is at current limit by:
(17)
Once the compensation resistor is known, set the zero formed
by the compensation capacitor and resistor to one-fourth of the
crossover frequency, or
FB 2
C2 =
C SS = I SS
4746 × f C × C OUT × (VOUT ) 2
=
VIN
C COMP =
Solve for C2 as follows:
SOFT START CAPACITOR
Solve for RCOMP,
RCOMP =
The capacitor, C2, is chosen to cancel the zero introduced by
output capacitance, ESR.
Δt
VSS
(20)
where:
ISS = 5 μA (typical).
VSS = 1.2 V.
Δt = startup time, at current limit.
If the applied load does not place the part at current limit, the
necessary CSS will be smaller. A 33 nF soft start capacitor results
in negligible input current overshoot at start up, and therefore is
suitable for most applications. However, if an unusually large
output capacitor is used, a longer soft start period is required
to prevent input inrush current.
Conversely, if fast startup is a requirement, the soft start
capacitor can be reduced or removed, allowing the
ADP1612/ADP1613 to start quickly, but allowing greater
peak switch current.
Figure 35. Compensation Components
Rev. A | Page 15 of 28
ADP1612/ADP1613
TYPICAL APPLICATION CIRCUITS
The ADP1612 is geared toward applications requiring input
voltages as low as 1.8 V, where the ADP1613 is more suited for
applications needing the output power capabilities of a 2.0 A
switch. The primary differences are shown in Table 6.
STEP-UP REGULATOR CIRCUIT EXAMPLES
ADP1612 Step-Up Regulator
L1
4.7µH
D1
3A, 40V VOUT = 5V
VIN = 1.8V TO 4.2V
6
Table 6. ADP1612/ADP1613 Differences
ADP1612
1.4 A
1.8 V to 5.5 V
ADP1613
2.0 A
2.5 V to 5.5 V
3
EN
7
FREQ
8
SS
FB 2
COMP 1
CSS
33nF
The Step-Up Regulator Circuit Examples section recommends
component values for several common input, output, and load
conditions. The equations in the Applications Information
section can be used to select components for alternate
configurations.
EN
7
FREQ
VOUT
SW 5
R1
FB 2
1.3MHz
650kHz
(DEFAULT)
8
R2
COMP 1
SS
GND
CSS
COUT
RCOMP
4
70
60
50
CCOMP
VIN = 1.8V
VIN = 2.7V
VIN = 3.3V
VIN = 4.2V
40
06772-005
CIN
30
1
10
Figure 36. Step-Up Regulator
The modified step-up circuit in Figure 37 incorporates true
shutdown capability advantageous for battery-powered applications requiring low standby current. Driving the EN pin below
0.3 V shuts down the ADP1612/ADP1613 and completely
disconnects the input from the output.
L1
VIN
Q1
ADP1612/
ADP1613
A
6 VIN
R3
10kΩ
8 SS
ON
OFF
CSS
1k
10k
Figure 39. ADP1612 Efficiency vs. Load Current
VOUT = 5 V, fSW = 650 kHz
T
VOUT = 5V
fSW = 650kHz
OUTPUT VOLTAGE (50mV/DIV)
AC-COUPLED
VOUT
LOAD CURRENT (50mA/DIV)
FB 2
1.3MHz
7 FREQ
650kHz
(DEFAULT)
Q1
B
100
LOAD CURRENT (mA)
R1
3 EN
CIN
D1
SW 5
R2
COMP 1
GND
4
RCOMP
CCOMP
COUT
06772-006
NTGD1100L
ADP1612
Figure 37. Step-Up Regulator with True Shutdown
Rev. A | Page 16 of 28
TIME (100µs/DIV)
Figure 40. ADP1612 50 mA to 150 mA Load Transient (VIN = 3.3 V)
VOUT = 5 V, fSW = 650 kHz
06772-041
3
CCOMP: ECJ-2VB1H332K
CIN: GRM21BR61C106KE15L
COUT: GRM32DR71E106KA12L
CSS: ECJ-2VB1H333K
80
D1
ON
OFF
RCOMP
6.8kΩ
CCOMP
3300pF
VOUT = 5V
fSW = 650kHz
TA = 25°C
90
EFFICIENCY (%)
VIN
COUT
10µF
100
L1
6
4
R2
10kΩ
Figure 38. ADP1612 Step-Up Regulator Configuration
VOUT = 5 V, fSW = 650 kHz
The circuit in Figure 36 shows the ADP1612/ADP1613 in a
basic step-up configuration.
ADP1612/
ADP1613
GND
L1: DO3316P-472ML
D1: MBRA340T3G
R1: RC0805FR-0730KL
R2: CRCW080510K0FKEA
RCOMP: RC0805JR-076K8L
STEP-UP REGULATOR
VIN
R1
30kΩ
06772-042
Parameter
Current Limit
Input Voltage Range
OFF
CIN
10µF
SW 5
VIN
ADP1612
ON
06772-040
Both the ADP1612 and ADP1613 can be used in the application
circuits in this section.
ADP1612/ADP1613
L1
4.7µH
L1
10µH
OFF
CIN
10µF
SW 5
VIN
ADP1612
3
EN
7
FREQ
8
SS
6
R1
30kΩ
FB 2
COMP 1
CSS
33nF
GND
4
L1: DO3316P-472ML
D1: MBRA340T3G
R1: RC0805FR-0730KL
R2: CRCW080510K0FKEA
RCOMP: RC0805JR-0712KL
R2
10kΩ
OFF
CIN
10µF
COUT
10µF
SW 5
VIN
ADP1612
ON
3
EN
7
FREQ
8
SS
COMP 1
CSS
33nF
CCOMP: ECJ-2VB1H122K
CIN: GRM21BR61C106KE15L
COUT: GRM32DR71E106KA12L
CSS: ECJ-2VB1H333K
R1
86.6kΩ
FB 2
RCOMP
12kΩ
CCOMP
1200pF
GND
4
L1: DO3316P-103ML
D1: DFLS220L-7
R1: ERJ-6ENF8662V
R2: CRCW080510K0FKEA
RCOMP: RC0805JR-0722KL
06772-043
6
ON
D1
2A, 20V VOUT = 12V
VIN = 2.7V TO 5V
Figure 41. ADP1612 Step-Up Regulator Configuration
VOUT = 5 V, fSW = 1.3 MHz
COUT
10µF
R2
10kΩ
RCOMP
22kΩ
CCOMP
1800pF
CCOMP: ECJ-2VB1H182K
CIN: GRM21BR61C106KE15L
COUT: GRM32DR71E106KA12L
CSS: ECJ-2VB1H333K
06772-046
D1
3A, 40V V
OUT = 5V
VIN = 1.8V TO 4.2V
Figure 44. ADP1612 Step-Up Regulator Configuration
VOUT = 12 V, fSW = 650 kHz
100
100
ADP1612
VOUT = 5V
fSW = 1.3MHz
TA = 25°C
90
ADP1612
VOUT = 12V
fSW = 650kHz
TA = 25°C
90
EFFICIENCY (%)
EFFICIENCY (%)
80
70
60
80
70
60
50
100
LOAD CURRENT (mA)
1k
10k
40
1
Figure 42. ADP1612 Efficiency vs. Load Current
VOUT = 5 V, fSW = 1.3 MHz
T
1k
Figure 45. ADP1612 Efficiency vs. Load Current
VOUT = 12 V, fSW = 650 kHz
T
VOUT = 5V
fSW = 1.3MHz
OUTPUT VOLTAGE (50mV/DIV)
AC-COUPLED
VOUT = 12V
fSW = 650kHz
OUTPUT VOLTAGE (100mV/DIV)
AC-COUPLED
LOAD CURRENT (50mA/DIV)
06772-045
LOAD CURRENT (50mA/DIV)
TIME (100µs/DIV)
10
100
LOAD CURRENT (mA)
TIME (100µs/DIV)
Figure 43. ADP1612 50 mA to 150 mA Load Transient (VIN = 3.3 V)
VOUT = 5 V, fSW = 1.3 MHz
06772-048
10
06772-044
30
1
VIN = 2.7V
VIN = 3.3V
VIN = 4.2V
VIN = 5.0V
50
06772-047
VIN = 1.8V
VIN = 2.7V
VIN = 3.3V
VIN = 4.2V
40
Figure 46. ADP1612 50 mA to 150 mA Load Transient (VIN = 3.3 V)
VOUT = 12 V, fSW = 650 kHz
Rev. A | Page 17 of 28
ADP1612/ADP1613
L1
6.8µH
L1
15µH
OFF
CIN
10µF
SW 5
VIN
ADP1612
3
EN
7
FREQ
8
SS
6
FB 2
COMP 1
CSS
33nF
GND
4
L1: DO3316P-682ML
D1: DFLS220L-7
R1: ERJ-6ENF8662V
R2: CRCW080510K0FKEA
RCOMP: RC0805JR-0718KL
COUT
10µF
R2
10kΩ
OFF
CIN
10µF
SW 5
VIN
ADP1612
ON
R1
86.6kΩ
3
EN
7
FREQ
8
SS
COMP 1
CSS
33nF
CCOMP: CC0805KRX7R9BB681
CIN: GRM21BR61C106KE15L
COUT: GRM32DR71E106KA12L
CSS: ECJ-2VB1H333K
R1
110kΩ
FB 2
RCOMP
18kΩ
CCOMP
680pF
GND
4
L1: DO3316P-153ML
D1: DFLS220L-7
R1: ERJ-6ENF1103V
R2: CRCW080510K0FKEA
RCOMP: RC0805JR-0722KL
06772-049
6
ON
D1
2A, 20V VOUT = 15V
VIN = 2.7V TO 5V
Figure 47. ADP1612 Step-Up Regulator Configuration
VOUT = 12 V, fSW = 1.3 MHz
COUT
10µF
R2
10kΩ
RCOMP
22kΩ
CCOMP
1800pF
CCOMP: ECJ-2VB1H182K
CIN: GRM21BR61C106KE15L
COUT: GRM32DR71E106KA12L
CSS: ECJ-2VB1H333K
06772-052
D1
2A, 20V VOUT = 12V
VIN = 2.7V TO 5V
Figure 50. ADP1612 Step-Up Regulator Configuration
VOUT = 15 V, fSW = 650 kHz
100
100
ADP1612
VOUT = 12V
fSW = 1.3MHz
TA = 25°C
90
ADP1612
VOUT = 15V
fSW = 650kHz
TA = 25°C
90
EFFICIENCY (%)
EFFICIENCY (%)
80
70
60
80
70
60
50
1k
40
1
Figure 48. ADP1612 Efficiency vs. Load Current
VOUT = 12 V, fSW = 1.3 MHz
T
1k
Figure 51. ADP1612 Efficiency vs. Load Current
VOUT = 15 V, fSW = 650 kHz
VOUT = 12V
fSW = 1.3MHz
T
OUTPUT VOLTAGE (100mV/DIV)
AC-COUPLED
VOUT = 15V
fSW = 650kHz
OUTPUT VOLTAGE (200mV/DIV)
AC-COUPLED
LOAD CURRENT (50mA/DIV)
06772-051
LOAD CURRENT (50mA/DIV)
TIME (100µs/DIV)
10
100
LOAD CURRENT (mA)
TIME (100µs/DIV)
Figure 49. ADP1612 50 mA to 150 mA Load Transient (VIN = 3.3 V)
VOUT = 12 V, fSW = 1.3 MHz
06772-054
10
100
LOAD CURRENT (mA)
06772-050
30
1
VIN = 2.7V
VIN = 3.3V
VIN = 4.2V
VIN = 5.0V
50
06772-053
VIN = 2.7V
VIN = 3.3V
VIN = 4.2V
VIN = 5.0V
40
Figure 52. ADP1612 50 mA to 150 mA Load Transient (VIN = 3.3 V)
VOUT = 15 V, fSW = 650 kHz
Rev. A | Page 18 of 28
ADP1612/ADP1613
ADP1613 Step-Up Regulator
L1
10µH
L1
10µH
OFF
CIN
10µF
SW 5
VIN
ADP1612
3
EN
7
FREQ
8
SS
6
R1
110kΩ
FB 2
COMP 1
CSS
33nF
GND
4
L1: DO3316P-103ML
D1: DFLS220L-7
R1: ERJ-6ENF1103V
R2: CRCW080510K0FKEA
RCOMP: RC0805JR-0710KL
COUT
10µF
R2
10kΩ
OFF
CIN
10µF
3
EN
7
FREQ
8
SS
COMP 1
RCOMP
10kΩ
CCOMP
1800pF
CSS
33nF
CCOMP: ECJ-2VB1H182K
CIN: GRM21BR61C106KE15L
COUT: GRM32DR71E106KA12L
CSS: ECJ-2VB1H333K
R1
86.6kΩ
FB 2
GND
4
L1: DO3316P-103ML
D1: MBRA340T3G
R1: ERJ-6ENF8662V
R2: CRCW080510K0FKEA
RCOMP: RC0805JR-0712KL
Figure 53. ADP1612 Step-Up Regulator Configuration
VOUT =15 V, fSW = 1.3 MHz
COUT
10µF
R2
10kΩ
RCOMP
12kΩ
CCOMP
2200pF
CCOMP: ECJ-2VB1H222K
CIN: GRM21BR61C106KE15L
COUT: GRM32DR71E106KA12L
CSS: ECJ-2VB1H333K
Figure 56. ADP1613 Step-Up Regulator Configuration
VOUT = 12 V, fSW = 650 kHz
100
100
ADP1613
VOUT = 12V
fSW = 650kHz
TA = 25°C
ADP1612
VOUT = 15V
fSW = 1.3MHz
TA = 25°C
90
90
80
EFFICIENCY (%)
80
70
60
70
60
50
VIN = 2.7V
VIN = 3.3V
VIN = 4.2V
VIN = 5.0V
30
1
10
100
LOAD CURRENT (mA)
1k
30
1
T
VOUT = 15V
fSW = 1.3MHz
1k
VOUT = 12V
fSW = 650kHz
OUTPUT VOLTAGE (200mV/DIV)
AC-COUPLED
OUTPUT VOLTAGE (200mV/DIV)
AC-COUPLED
LOAD CURRENT (50mA/DIV)
LOAD CURRENT (50mA/DIV)
06772-057
TIME (100µs/DIV)
10
100
LOAD CURRENT (mA)
Figure 57. ADP1613 Efficiency vs. Load Current
VOUT = 12 V, fSW = 650 kHz
Figure 54. ADP1612 Efficiency vs. Load Current
VOUT =15 V, fSW = 1.3 MHz
T
VIN = 2.7V
VIN = 3.3V
VIN = 4.2V
VIN = 5.0V
40
06772-056
40
TIME (100µs/DIV)
Figure 55. ADP1612 50 mA to 150 mA Load Transient (VIN = 3.3 V)
VOUT =15 V, fSW = 1.3 MHz
Figure 58. ADP1613 50 mA to 150 mA Load Transient (VIN = 5 V)
VOUT = 12 V, fSW = 650 kHz
Rev. A | Page 19 of 28
06772-059
50
06772-060
EFFICIENCY (%)
SW 5
VIN
ADP1613
ON
06772-055
6
ON
D1
3A, 40V VOUT = 12V
VIN = 2.7V TO 5V
06772-058
D1
2A, 20V VOUT = 15V
VIN = 2.7V TO 5V
ADP1612/ADP1613
L1
6.8µH
L1
15µH
OFF
CIN
10µF
SW 5
VIN
ADP1613
3
EN
7
FREQ
8
SS
6
FB 2
COMP 1
CSS
33nF
GND
4
L1: DO3316P-682ML
D1: MBRA340T3G
R1: ERJ-6ENF8662V
R2: CRCW080510K0FKEA
RCOMP: RC0805JR-0710KL
COUT
10µF
R2
10kΩ
3
EN
7
FREQ
8
SS
COMP 1
CSS
33nF
CCOMP: ECJ-2VB1H102K
CIN: GRM21BR61C106KE15L
COUT: GRM32DR71E106KA12L
CSS: ECJ-2VB1H333K
R1
110kΩ
FB 2
RCOMP
10kΩ
CCOMP
1000pF
GND
4
L1: DO3316P-153ML
D1: MBRA340T3G
R1: ERJ-6ENF1103V
R2: CRCW080510K0FKEA
RCOMP: RC0805JR-0710KL
Figure 59. ADP1613 Step-Up Regulator Configuration
VOUT = 12 V, fSW = 1.3 MHz
R2
10kΩ
COUT
10µF
RCOMP
10kΩ
CCOMP
1800pF
CCOMP: ECJ-2VB1H182K
CIN: GRM21BR61C106KE15L
COUT: GRM32DR71E106KA12L
CSS: ECJ-2VB1H333K
Figure 62. ADP1613 Step-Up Regulator Configuration
VOUT = 15 V, fSW = 650 kHz
100
100
ADP1613
VOUT = 12V
fSW = 1.3MHz
TA = 25°C
90
ADP1613
VOUT = 15V
fSW = 650kHz
TA = 25°C
90
80
EFFICIENCY (%)
80
70
60
70
60
50
VIN = 2.7V
VIN = 3.3V
VIN = 4.2V
VIN = 5.0V
30
10
100
LOAD CURRENT (mA)
1k
30
1
Figure 60. ADP1613 Efficiency vs. Load Current
VOUT = 12 V, fSW = 1.3 MHz
T
1k
Figure 63. ADP1613 Efficiency vs. Load Current
VOUT = 15 V, fSW = 650 kHz
T
VOUT = 12V
fSW = 1.3MHz
OUTPUT VOLTAGE (100mV/DIV)
AC-COUPLED
VOUT = 15V
fSW = 650kHz
OUTPUT VOLTAGE (200mV/DIV)
AC-COUPLED
LOAD CURRENT (50mA/DIV)
TIME (100µs/DIV)
10
100
LOAD CURRENT (mA)
LOAD CURRENT (50mA/DIV)
TIME (100µs/DIV)
Figure 61. ADP1613 50 mA to 150 mA Load Transient (VIN = 5 V)
VOUT = 12 V, fSW = 1.3 MHz
06772-066
1
VIN = 3.3V
VIN = 4.2V
VIN = 5.0V
VIN = 5.5V
40
06772-062
40
Figure 64. ADP1613 50 mA to 150 mA Load Transient (VIN = 5 V)
VOUT = 15 V, fSW = 650 kHz
Rev. A | Page 20 of 28
06772-065
50
06772-063
EFFICIENCY (%)
OFF
CIN
10µF
SW 5
VIN
ADP1613
ON
R1
86.6kΩ
06772-061
6
ON
D1
3A, 40V VOUT = 15V
VIN = 3.3V TO 5.5V
06772-064
D1
3A, 40V VOUT = 12V
VIN = 2.7V TO 5V
ADP1612/ADP1613
L1
10µH
L1
15µH
OFF
CIN
10µF
SW 5
VIN
ADP1613
3
EN
7
FREQ
8
SS
6
FB 2
COMP 1
CSS
33nF
GND
4
L1: DO3316P-103ML
D1: MBRA340T3G
R1: ERJ-6ENF1103V
R2: CRCW080510K0FKEA
RCOMP: RC0805JR-078K2L
R2
10kΩ
COUT
10µF
3
EN
7
FREQ
8
SS
COMP 1
CSS
33nF
CCOMP: ECJ-2VB1H122K
CIN: GRM21BR61C106KE15L
COUT: GRM32DR71E106KA12L
CSS: ECJ-2VB1H333K
R1
150kΩ
FB 2
RCOMP
8.2kΩ
CCOMP
1200pF
GND
4
L1: DO3316P-153ML
D1: MBRA340T3G
R1: RC0805JR-07150KL
R2: CRCW080510K0FKEA
RCOMP: RC0805JR-0718KL
Figure 65. ADP1613 Step-Up Regulator Configuration
VOUT = 15 V, fSW = 1.3 MHz
R2
10kΩ
COUT
10µF
RCOMP
18kΩ
CCOMP
820pF
CCOMP: CC0805KRX7R9BB821
CIN: GRM21BR61C106KE15L
COUT: GRM32DR71E106KA12L
CSS: ECJ-2VB1H333K
Figure 68. ADP1613 Step-Up Regulator Configuration
VOUT = 20 V, fSW = 650 kHz
100
100
ADP1613
VOUT = 15V
fSW = 1.3MHz
TA = 25°C
90
ADP1613
VOUT = 20V
fSW = 650kHz
TA = 25°C
90
80
EFFICIENCY (%)
80
70
60
50
70
60
50
20
1
10
100
LOAD CURRENT (mA)
1k
30
06772-068
30
1
Figure 66. ADP1613 Efficiency vs. Load Current
VOUT = 15 V, fSW = 1.3 MHz
T
10
100
LOAD CURRENT (mA)
1k
Figure 69. ADP1613 Efficiency vs. Load Current
VOUT = 20 V, fSW = 650 kHz
T
VOUT = 15V
fSW = 1.3MHz
OUTPUT VOLTAGE (200mV/DIV)
AC-COUPLED
VOUT = 20V
fSW = 650kHz
OUTPUT VOLTAGE (200mV/DIV)
AC-COUPLED
LOAD CURRENT (50mA/DIV)
LOAD CURRENT (50mA/DIV)
TIME (100µs/DIV)
VIN = 3.3V
VIN = 4.2V
VIN = 5.0V
VIN = 5.5V
40
TIME (100µs/DIV)
Figure 67. ADP1613 50 mA to 150 mA Load Transient (VIN = 5 V)
VOUT = 15 V, fSW = 1.3 MHz
Figure 70. ADP1613 50 mA to 150 mA Load Transient (VIN = 5 V)
VOUT = 20 V, fSW = 650 kHz
Rev. A | Page 21 of 28
06772-071
VIN = 3.3V
VIN = 4.2V
VIN = 5.0V
VIN = 5.5V
06772-072
40
06772-069
EFFICIENCY (%)
OFF
CIN
10µF
SW 5
VIN
ADP1613
ON
R1
110kΩ
06772-067
6
ON
D1
3A, 40V VOUT = 20V
VIN = 3.3V TO 5.5V
06772-070
D1
3A, 40V VOUT = 15V
VIN = 3.3V TO 5.5V
ADP1612/ADP1613
SEPIC CONVERTER
L1
10µH
ADP1613
3
EN
7
FREQ
8
SS
R1
150kΩ
FB 2
COMP 1
CSS
33nF
GND
4
L1: DO3316P-103ML
D1: MBRA340T3G
R1: RC0805JR-07150KL
R2: CRCW080510K0FKEA
RCOMP: RC0805JR-078K2L
R2
10kΩ
COUT
10µF
RCOMP
8.2kΩ
CCOMP
1200pF
CCOMP: ECL-2VB1H122K
CIN: GRM21BR61C106KE15L
COUT: GRM32DR71E106KA12L
CSS: ECJ-2VB1H333K
Figure 71. ADP1613 Step-Up Regulator Configuration
VOUT = 20 V, fSW = 1.3 MHz
The input and the output are dc isolated by a coupling capacitor
(C1). In steady state, the average voltage of C1 is the input voltage.
When the ADP1612/ADP1613 switch turns on and the diode
turns off, the input voltage provides energy to L1 and C1 provides
energy to L2. When the ADP1612/ADP1613 switch turns off
and the diode turns on, the energy in L1 and L2 is released to
charge the output capacitor (COUT) and the coupling capacitor
(C1) and to supply current to the load.
L1
DO3316P
4.7µH
100
ADP1613
VOUT = 20V
fSW = 1.3MHz
TA = 25°C
90
6
VIN
3
EN
7
FREQ
8
SS
C1
10µF
CIN
10µF
OFF
60
50
CSS
40
VIN = 3.3V
VIN = 4.2V
VIN = 5.0V
VIN = 5.5V
1
10
100
LOAD CURRENT (mA)
1k
L2
DO3316P
4.7µH
R1
16.9kΩ
FB 2
COMP 1
GND
4
RCOMP
82kΩ
R2
10kΩ
COUT
10µF
CCOMP
220pF
TFT LCD BIAS SUPPLY
Figure 75 shows a power supply circuit for TFT LCD module
applications. This circuit has +10 V, −5 V, and +22 V outputs.
The +10 V is generated in the step-up configuration. The −5 V
and +22 V are generated by the charge-pump circuit. During
the step-up operation, the SW node switches between +10 V
and ground (neglecting the forward drop of the diode and on
resistance of the switch). When the SW node is high, C5 charges
up to +10 V. When the SW node is low, C5 holds its charge and
forward-biases D8 to charge C6 to −10 V. The Zener diode (D9)
clamps and regulates the output to −5 V.
Figure 72. ADP1613 Efficiency vs. Load Current
VOUT = 20 V, fSW = 1.3 MHz
T
VOUT = 3.3V
Figure 74. SEPIC Converter
20
06772-074
30
MBRA210LT
2A, 10V
SW 5
ON
70
VOUT = 20V
fSW = 1.3MHz
OUTPUT VOLTAGE (200mV/DIV)
AC-COUPLED
LOAD CURRENT (50mA/DIV)
The VGH output is generated in a similar manner by the chargepump capacitors, C1, C2, and C4. The output voltage is tripled
and regulated down to 22 V by the Zener diode, D5.
TIME (100µs/DIV)
06772-075
EFFICIENCY (%)
ADP1612/
ADP1613
VIN = 2.0V TO 5.5V
80
Figure 73. ADP1613 50 mA to 150 mA Load Transient (VIN = 5 V)
VOUT = 20 V, fSW = 1.3 MHz
Rev. A | Page 22 of 28
06772-008
OFF
SW 5
VIN
06772-073
6
ON
CIN
10µF
The circuit in Figure 74 shows the ADP1612/ADP1613 in a
single-ended primary inductance converter (SEPIC) topology.
This topology is useful for an unregulated input voltage, such as
a battery-powered application in which the input voltage can vary
between 2.7 V to 5 V and the regulated output voltage falls within
the input voltage range.
D1
3A, 40V VOUT = 20V
VIN = 3.3V TO 5.5V
ADP1612/ADP1613
BAV99
R4
200Ω
VGL
–5V
D8
C6
10µF
D9
BZT52C5VIS
R3
200Ω
D5
C4
10nF
BAV99
C3
10µF
C5
10nF
D5
BZT52C22
VGH
+22V
D4
D7
C1
10nF
BAV99
D3
C2
1µF
DO3316P
4.7µH
D2
ADP1612/
ADP1613
VIN = 3.3V
6
VIN
3
EN
7
FREQ
8
SS
D1
ON
OFF
R1
71.5kΩ
FB 2
1.3MHz
650kHz
(DEFAULT)
CSS
R2
10kΩ
COMP 1
GND
4
RCOMP
27kΩ
CCOMP
1200pF
Figure 75. TFT LCD Bias Supply
Rev. A | Page 23 of 28
COUT
10µF
06772-007
CIN
10µF
VOUT = 10V
SW 5
ADP1612/ADP1613
PCB LAYOUT GUIDELINES
For high efficiency, good regulation, and stability, a welldesigned printed circuit board layout is required.
Use the following guidelines when designing printed circuit
boards (also see Figure 34 for a block diagram and Figure 3
for a pin configuration).
•
•
•
06772-076
•
•
Figure 76. Example Layout for ADP1612/ADP1613 Boost Application
(Top Layer)
•
•
06772-077
•
Figure 77. Example Layout for ADP1612/ADP1613 Boost Application
(Bottom Layer)
Rev. A | Page 24 of 28
Keep the low ESR input capacitor, CIN (labeled as C7 in
Figure 76), close to VIN and GND. This minimizes noise
injected into the part from board parasitic inductance.
Keep the high current path from CIN (labeled as C7 in
Figure 76) through the L1 inductor to SW and GND as
short as possible.
Keep the high current path from VIN through L1, the
rectifier (D1) and the output capacitor, COUT (labeled as
C4 in Figure 76) as short as possible.
Keep high current traces as short and as wide as possible.
Place the feedback resistors as close to FB as possible to
prevent noise pickup. Connect the ground of the feedback
network directly to an AGND plane that makes a Kelvin
connection to the GND pin.
Place the compensation components as close as possible to
COMP. Connect the ground of the compensation network
directly to an AGND plane that makes a Kelvin connection
to the GND pin.
Connect the softstart capacitor, CSS (labeled as C1 in
Figure 76) as close to the device as possible. Connect the
ground of the softstart capacitor to an AGND plane that
makes a Kelvin connection to the GND pin.
Avoid routing high impedance traces from the compensation and feedback resistors near any node connected to SW
or near the inductor to prevent radiated noise injection.
ADP1612/ADP1613
OUTLINE DIMENSIONS
3.20
3.00
2.80
8
3.20
3.00
2.80
1
5.15
4.90
4.65
5
4
PIN 1
IDENTIFIER
0.65 BSC
0.95
0.85
0.75
15° MAX
1.10 MAX
0.40
0.25
6°
0°
0.23
0.13
COMPLIANT TO JEDEC STANDARDS MO-187-AA
0.70
0.55
0.40
091709-A
0.15
0.05
COPLANARITY
0.10
Figure 78. 8-Lead Mini Small Outline Package [MSOP]
(RM-8)
Dimensions shown in millimeters
ORDERING GUIDE
Model
ADP1612ARMZ-R7 1
ADP1613ARMZ-R71
ADP1612-5-EVALZ1
ADP1612-BL1-EVZ1
ADP1613-12-EVALZ1
ADP1613-BL1-EVZ1
1
Temperature Range
−40°C to +125°C
−40°C to +125°C
Package Description
8-Lead Mini Small Outline Package [MSOP]
8-Lead Mini Small Outline Package [MSOP]
Evaluation Board, 5 V Output Voltage Configuration
Blank Evaluation Board
Evaluation Board, 12 V Output Voltage Configuration
Blank Evaluation Board
Z = RoHS Compliant Part.
Rev. A | Page 25 of 28
Package Option
RM-8
RM-8
Branding
L7Z
L96
ADP1612/ADP1613
NOTES
Rev. A | Page 26 of 28
ADP1612/ADP1613
NOTES
Rev. A | Page 27 of 28
ADP1612/ADP1613
NOTES
©2009 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D06772-0-9/09(A)
Rev. A | Page 28 of 28
Similar pages